


It's All Relative

by flipflop_diva, froggyfun365



Category: Harry Potter - J. K. Rowling, Percy Jackson and the Olympians & Related Fandoms - All Media Types
Genre: Action/Adventure, Audio Format: M4B, Audio Format: MP3, Audio Format: Streaming, Collaboration, Community: pod_together, Crossover, Crossovers & Fandom Fusions, Download Available, F/F, F/M, HP: EWE, Long Lost/Secret Relatives, Music, Podfic, Podfic & Podficced Works, Podfic Available, Podfic Length: 30-45 Minutes, Post-The Heroes of Olympus
Language: English
Status: Completed
Published: 2015-08-24
Updated: 2015-08-24
Packaged: 2018-04-10 15:58:39
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,494
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/4398161
Author URL: https://archiveofourown.org/users/flipflop_diva/pseuds/flipflop_diva, https://archiveofourown.org/users/froggyfun365/pseuds/froggyfun365
Summary: <blockquote class="userstuff">
              <p>Professor Trelawney's prophecy about Luna really did seem crazy on the surface. But it was about to change everything she thought she ever knew about her life. (A crossover with the Percy Jackson/Heroes of Olympus series.)</p>
            </blockquote>





	It's All Relative

**Author's Note:**

> Author's notes: I just want to thank froggyfun365 for being an awesome partner! Seriously, she put up with way more false starts and last-minute additions then she should ever have had to, but she stuck around, was always awesome and made a wonderful podfic that you all should listen to! So thank you froggyfun365, and to everyone else, I hope you enjoy!

[MP3](http://k001.kiwi6.com/hotlink/jeh9kvtvag/It_s_All_Relative.mp3)

Podfic also available for streaming or download: [HERE](https://app.box.com/s/djm81a6turel2wmw92xt83l1u76i3bqx). Duration: 00:30:02, 27.5 MB. Enjoy!

Comments are love! <3

\-------------------------------------------------------------------------------------------------------------------

“I think we should go to New York.”

At Luna’s words, Hermione looked up from her spot on the floor, putting the book she was reading down on the ground beside her. “Luna,” she said, her voice gentle but her eyes almost pitying, “I thought we talked about this.”

“We did,” Luna said. “I think we should go.”

“We shouldn’t go all the way to America because of some ridiculous prophecy — if it’s even a prophecy, which I highly doubt.”

Luna smiled at her girlfriend. She loved Hermione partly for the way her mind worked, but she never could see all the possibilities of the world. It was no surprise she didn’t see the possibilities in this either. 

“We do not know if it’s ridiculous,” Luna told her now.

Hermione started to roll her eyes, but stopped as she realized Luna was serious. Instead she frowned. 

“Greek gods,” she said softly. “We’re talking about Greek gods.”

“Yes, we are.”

“They aren’t real. They’re myths. Legends. Stories people made up to explain things because they didn’t know the real truth.”

“You’re Muggle-born,” Luna said. “You once thought wizards and witches were a myth.”

“Yes, but …”

“It’s the same thing.”

“It’s not.”

“Why?” Luna gazed at her, at the stubborn expression on her face. “Because this you don’t believe?”

“Because we would know if it were true!” Hermione argued. “The Ministry knows these things!”

Luna shrugged. “Muggles don’t know about us. Maybe they keep themselves a secret too.”

“Luna …” Hermione frowned, running a hand through her long hair. “Don’t you understand what this would mean? It would mean your mother isn’t who you thought she was.”

“Maybe she isn’t.”

“But you knew her!”

“Did I?” Luna cocked her head to the side. “She died when I was young. My memories of her are so vague. Would this not explain why?”

Hermione shook her head. “Come on,” she said. “I know you believe in so many things other people don’t, and I love you for that, but are you honestly sitting there telling me you think your mother might be a Greek goddess just because Professor Trelawney stopped you on the street one day last week and told you so?”

“People aren’t wrong just because we want them to be,” Luna said simple.

“But she’s always wrong!”

“Not always. She was right about Harry.”

Hermione closed her eyes. Luna watched as the fight almost visibly drained out of her. She couldn’t argue with that.

Luna slid off the bed where she had been sitting and joined Hermione on the floor, reaching out to take her hand. 

“I need to know,” she said. “Can you not understand that?”

“Luna …”

“Maybe this will explain why I’ve always felt so different.”

Hermione’s eyes turned sad, but Luna squeezed her hand before she could talk. “It’s not a bad thing,” she told her. “I like who I am. I just need to know.”

Hermione didn’t say anything for a while, but finally, she nodded. “Okay,” she said. “We can go to New York.”

Luna smiled. “I have always wanted to see that Empire State Building. I hear it might even house a Whirly Whumpintail.”

Beside her, Hermione laughed.

•••

“You know, when we talked about going back to New York and seeing my mom for her birthday, I remember thinking, ‘Hey, that would be fun. It’s been awhile. It’d be fun to see New York again.’ You didn’t happen to mention that ‘seeing New York’ actually meant seeing every single store on this block for ten hours at a time.” Percy sighed extra loudly — and extra long. “Can’t we stop for a few minutes?”

He just managed to dodge Annabeth’s flying shopping bag before it smacked him across the head. Which maybe he deserved, but dang, she’d bought shoes. Those would totally have left a mark.

“That’s not very nice,” he grumbled as Annabeth glared.

“You didn’t have to come with me,” she said. “Piper offered to come. You just didn’t want to be stuck with your mom while she lectured you about why we don’t visit more often.”

Okay, so she had a point. He really hadn’t wanted that lecture. And he knew it was coming. His mom was fully supportive of their decision to live in New Rome — except when it was more than two months since a visit. As though he could just snap his fingers and be on the other side of the country. But his mom apparently thought he could.

“Do you know how many times in the past couple years I’ve thought you were dead?” his mom had already started the night they’d arrived. “The least you could do is visit like you promised you would!”

“Okay, fine,” Percy said to Annabeth now. “But can’t we just get some food or something before we keep going? I just need to refuel.”

She rolled her eyes. “If we stop, you have to carry the packages.”

“I don’t see how that’s fair.”

“You can head home to your mom. The subway is right over there.” She pointed.

“Okay, okay, I’ll carry your packages,” Percy grumbled as Annabeth smirked. He honestly didn’t understand how she always seemed to win these little fights, but it was just part of her charm.

At least he could sit down in a few minutes, if they could just find some food they agreed on.

He was so busy trying to find a restaurant that had comfortable looking chairs that he didn’t even realize Annabeth had stopped until he turned around to ask her if the one on the corner was okay and discovered she was still halfway back down the block. Which was weird.

He headed back toward her, concern building with each step. She seemed to be looking at something, or someone, across the street. For a moment he wondered if it was some new sort of monster out to get them.

“Annabeth,” he said, touching her on the arm when she didn’t respond to him after the first three tries.

This time she started, jerking around to look at him. Her eyes were wide and her face looked a little pale. She looked almost like how he imagined someone would look if they’d just seen a ghost. He almost glanced around to make sure she hadn’t, but instead he just asked, “What did you see?”

Slowly she turned and pointed. Percy followed her finger, but all he could see were two girls on the other side of the street, one blonde and one brunette. They were dressed slightly odd — the blonde looked like a rainbow had washed over her and the brunette looked like she was wearing a cape — but he couldn’t see any horns or claws or fangs or anything that might signal danger.

“I don’t get it,” he said to her.

“Me neither,” she said. “But the blonde girl. She looked at me and when our eyes met … it was the weirdest thing.”

“What happened?” Percy was wondering if a bolt of lightning maybe connected them or she’d seen a vision of the world ending. (Oh, gods, he hoped she hadn’t seen a vision of the world ending.) But when Annabeth answered it was neither of those things.

“I just got a feeling,” she said, “that she’s going to be very important.”

“Well,” Percy said slowly. “As long as she’s not a demon, I guess that’s okay.”

•••

New York was nothing like Luna had ever experienced. Not because it was a bustling city with people going anywhere and everywhere at all times of day or night. She had been to London many times, and her father had traveled with her to many big cities around the world — Paris, Munich, Rome. But none of them _felt_ like New York felt.

The second they had Apparated into a small grove in Central Park, tucked behind a grouping of trees, she had felt it. It was like her senses were on overdrive, her skin prickling. It was magic, Luna was sure of that, but it wasn’t _her_ magic. It was different. Older somehow. Powerful. 

“Where to?” Hermione had asked as they’d stepped out from their hiding place to see the city stretched before them. They had studied maps in Luna’s bedroom, but a map did not do justice to the amount of streets and buildings they could see in every direction.

But Luna hadn’t needed a map.

“The Empire State Building. It’s that way.” She had pointed straight ahead of her, as Hermione glanced at her sharply, clearly not convinced. But Luna just set off, letting the other girl follow along.

She couldn’t explain to Hermione how she knew. She couldn’t really even explain it to herself, but she had been taught since she was a young child that not everything in the world needed to be explained. It was something she had always believed in, and she trusted that instinct now.

They were halfway down Fifth Avenue when the tingling sensation she’d felt since they arrived had increased almost tenfold. It was like her whole body was buzzing, her senses trying to tell her something.

She stopped in her tracks, not caring if she was in anyone’s way, and took a look around her.

“Luna?” Hermione reached out and put a hand on her arm, concern lining her face. “What is it?”

“I’m not sure,” Luna murmured, but she kept searching the streets, the sidewalks, the people …

The people.

Across the street, a blonde girl was standing in the middle of the sidewalk, staring in their direction. Luna looked back toward her. It shouldn’t have been possible for their eyes to meet, not with the distance they were apart, but it was like time and space shrunk around them as they stared past each other’s eyes and into each other’s souls.

Luna gasped, staggered backward a few steps. She probably would have fallen if Hermione weren’t still grasping her arm.

“That girl,” Luna whispered.

Hermione turned. “Who are you talking about?” she said, a few seconds later. “Which girl?”

Luna shook her head to try and clear her mind, then peered around Hermione. She frowned. The blonde girl on the other side of the street was gone, lost into the crowd probably. It shouldn’t have been surprising with the quickness everyone on the streets seemed to travel, but that girl …

Luna shrugged at Hermione. “She’s gone.”

“Who was she?”

“I have no idea.”

Hermione sighed and pointed to a café just a few doors up. “Come on,” she said. “Let’s sit and eat and make a plan.”

“We have a plan.”

“We do not have a plan. The plan was to go to New York on the crazy words of Professor Trelawney, but then what?”

“I think that’s a very nice plan.”

“Luna …”

“But we can stop and get a beverage. I could use some water.”

Hermione shook her head in obvious annoyance, but she had won, so she led the way to the café.

“Tell me again,” Hermione said when they were seated with their drinks and sharing a large chocolate brownie between them, “what exactly Professor Trelawney said to you about coming to New York.”

Luna took a bite before answering. She knew exactly what Professor Trelawney had said, word for word, as she had repeated it to herself practically every minute of every day. “A child born in secret, no part of it was true. Part of two worlds, which one is really you? You’ll find the answers, in the Empire State. With a girl like you, you’ll meet your fate.”

Hermione frowned. “It sounds like jibberish.”

“It’s not,” Luna said. Hermione’s words sounded harsh, almost offensive, but Luna wasn’t offended in the least. She knew Hermione needed cold hard evidence to be convinced of anything. And she had a good feeling that evidence was coming soon.

“Well, let’s say it’s not,” Hermione conceded. “How do you know we’re in the right spot? That could mean anything.”

Luna smiled. “Because I know. You promised you would trust me. Just trust me.”

“I do trust you. I don’t trust Professor Trelawney.”

“Then it’s good you only have to trust me. Now come on. We have a really tall building to go visit.”

•••

Percy’s arms were dead. Almost literally. He actually wouldn’t be surprised if they just fell off his body and landed in a clump on the ground. Those shoes Annabeth had bought must have had weights in them or something. What else would explain how they could possibly weigh so much?

He shifted the packages and groaned as he hurried to catch up with his girlfriend. “You know I was just kidding when I said we should go say hi to our parents?” he panted.

Annabeth turned to look at him, an amused expression on her face. “We’re not inviting ourselves for dinner,” she said. “I just want to take a look at the place.”

“You can take a look right here. I see it perfectly clearly. Why do we have to walk by and peer in the door? Do you think your mom is going to be passing out tickets in the lobby?”

“Can’t I just be nostalgic?”

“No.”

“Okay, fine,” Annabeth said. “I want to see if I can find that girl again.”

“And you think she’s a typical tourist off to see the Empire State Building?”

Annabeth shrugged. “Not necessarily. I just …” She paused for a beat. “I just have a feeling.”

Well, okay, then. Percy couldn’t really argue with that, not when his feelings had led them to many things in the past. Maybe he could argue that they sometimes led to bad things, so they should just turn around now before she had to sacrifice some shoes, but he didn’t. He was, after all, the perfect supportive boyfriend who would walk by the Empire State Building just because Annabeth wanted them to — even if his arms fell off as he did so.

Of course, as his luck would have it, he should have listened to his gut. Like he really, _really_ should have listened to his gut.

It was all fun and games at first. They strolled along, Percy complaining and Annabeth giving him a hard time for it. They dodged tourists and people trying to force coupons and flyers into their hands. They listened to the comforting noise of taxi horns blaring and people cursing.

They slowed down as they approached the Empire State Building. The line, unsurprisingly for a warm May day, was long, people jammed up against each other waiting their turn. Annabeth stopped along the edges of the line and scanned the crowd. Percy did, too, but the rainbow-colored girl was nowhere that he could see.

He turned his head instead to look down the street. A couple blocks down, he could see someone walking what seemed like three gigantic dogs. They seemed to be moving pretty fast, like way faster than someone should be walking three gigantic dogs down a street filled with tourists.

He felt Annabeth tug on his hand — “Percy!” — but Percy was still staring at the three gigantic dogs. They seemed to be growing larger as they walked. They also seemed …

Oh, shit.

The three gigantic dogs were not being walked. There was no one walking them. They were just running toward the line at the Empire State Building.

Worse yet, those were _not_ three gigantic dogs.

“Hellhounds!” Percy yelled, dropping the packages to his feet, his hand automatically sliding into his pocket, searching for Riptide.

“What?” Annabeth’s hand was still in his, but he saw her turn in the direction he was facing.

“Oh, gods,” she whispered.

The dogs — the _hellhounds_ — were getting closer. Percy could see the bright red of their eyes. They were coming right for him and Annabeth, right for all the tourists in line.

People around them began to notice. Percy had no idea what they thought they saw. Maybe actual gigantic dogs who were not in a good mood. 

Percy yanked Riptide out of his pocket, still in pen form. Beside him, he saw Annabeth dig into her backpack for her own sword. But before he could even pull the top off his pen and unleash his weapon, something stranger than hellhounds attacking New York happened.

There was a blur of color off to his right, and as he watched, he saw a figure go racing toward the hellhounds. There was something in her hand, but he couldn’t quite make it out.

People in the crowd were screaming and running. A few children were crying. Percy and Annabeth ran toward the hellhounds, but the colorful figure was fast. Really fast.

One of the hellhounds stopped in its tracks and looked directly at the figure.

“Watch out!” Percy screamed as he tore toward her, yanking off the cap of Riptide at last and feeling the familiar weight of his sword in his hand.

The figure — he could see now it was the blonde girl from the street — kept moving toward the hellhounds, hand outstretched. She looked like she was holding a stick, but that didn’t make much sense, unless she thought these were dogs that wanted to play fetch.

“Wait!” Percy yelled as he kept racing toward the blonde girl, Annabeth on his heels.

The hellhound leaped. More people screamed. The girl waved the stick in her hand.

The next thing Percy knew, a red light flashed through the air and the hellhound toppled to the ground. Percy almost tripped over his own feet in shock.

Another flash of red light. Another hellhound down. The third hellhound seemed to want to take its chances. It leapt, eyes glowing, fangs beared. It, too, fell down beside its comrades, a flash of red light signaling its demise.

The hellhounds disappeared into the ground. The blonde girl turned around. She was just mere feet away from them now. Percy could see the stick in her hand wasn’t a stick. It was … well, it looked like a wand. An actual witch’s wand.

He stared at the blonde girl in disbelief, but it was Annabeth who spoke. 

“Who _are_ you?”

•••

It had all happened so fast. Luna and Hermione had been standing in line for the Empire State Building. Luna hadn’t known what she was expecting when she had arrived at the building, but there was nothing that seemed to call out for her.

So she had made a suggestion. “Let’s go up.” Maybe what they were looking for could only be seen from the air.

“Sure,” Hermione had said. “Why not?”

They had been in line for less than ten minutes. Hermione had pointed them out first. “Those dogs look really angry,” she’d said, frowning. “I don’t know why that owner is walking them so fast. There are children in the way!” She sounded angry. Luna peered around her to see.

Her eyes widened. “Those aren’t dogs.”

“What?” Hermione said. “Of course they are.”

They definitely weren’t. They were huge, bigger than any dog could possibly be, more like a small bear. And their eyes were red. Glowing. She would have recognized them anywhere.

Growling Helios.

She had seen them in her father’s news reports. He had never seen them, but he had described them perfectly. She knew exactly what to do.

“Stay here,” she told Hermione.

“Luna, what are you doing?”

Luna didn’t pay her any attention. She slipped under the rope dividing the line from the sidewalk and took off toward the Growling Helios, pulling her wand out from under her shirt as she went. She knew it was dangerous to use magic in public, but she couldn’t allow these awful creatures to hurt any innocent Muggles.

She could hear yelling around her and behind her, but Luna stayed focused. She wasn’t afraid of these creatures. 

They were coming toward her, getting faster the closer they got. The one in the lead caught her eye. Luna slowed down a little and waited.

The first Growling Helio jumped at her.

“ _Stupefy_!”

The creature went down in a flash of red light. The second one leaped. Then the third. She aimed at both of them, watched them both fall. She sucked in a lungful of air in relief and turned around. The blonde girl from earlier was standing behind her, with a boy of about the same age. They were both staring at her like she was an alien from outer space.

“Who are you?” the girl breathed. Her eyes focused on Luna’s wand. Luna quickly tucked it into her shirt. 

“You could _see_ those?” the boy asked.

Before Luna could answer, another figure emerged from the crowd of people, practically throwing herself at Luna.

Hermione.

“Luna!” Hermione’s eyes were almost wild looking. “What did you just do? You just killed someone’s dogs _with magic_?” She lowered her voice for the last two words, but Luna had a feeling the blonde girl and the boy had heard her.

“Those weren’t dogs,” Luna said, frowning at her girlfriend.

“Of course they were dogs!”

Luna shook her head. “They were Growling Helios,” she said. “Their eyes were glowing. They were as big as bears.”

Hermione stared at her like she had lost her mind. “What?” she said. “Luna. _They were regular dogs._ Ferocious dogs, but _dogs_.”

“They were hellhounds.” It was the boy who spoke. Hermione whirled around, but he was looking at Luna. “You could see them,” he repeated.

“Of course I could see them,” Luna said. She looked at Hermione. “I don’t understand what’s happening.”

“I do,” said the blonde girl. “You’re a demigod.”

“A what?” Hermione said, but Luna understood. In a split second, it made sense. Everything made sense. It was what Professor Trelawney had told her back in London. She was part Greek, and the force moving inside her was as ancient and powerful as it felt.

“My mother,” she whispered, her mind piecing it all together. “She was a Greek goddess. I am the child of a Greek goddess. It’s true. What Professor Trelawney said is true.”

The blonde girl pointed at Luna. “What you were holding. That was a real wand? A real _magic_ wand?”

“No,” Hermione said quickly, but Luna nodded. She didn’t know why, but she trusted these two strangers.

“Magic,” the blonde girl said. “I thought it was a myth.”

“Okay.” Hermione interrupted, looking between the blonde girl and the boy and Luna. “What the bloody heck is going on here?”

The blonde girl smiled. “I think we have a lot to talk about.”

•••

Percy wouldn’t go so far as to say it was the weirdest revelation of his life. He probably wouldn’t even go as far as to say it was in the top ten. He had had a _lot_ of weird revelations in his life, but he could certainly say this was one he would never have been expecting.

The rainbow girl was named Luna. Her undemigod friend was Hermione. They were both witches. Like honest to gods witches, who could wave wands and cast spells and move objects through the air and kill hellhounds in a matter of seconds.

Percy really couldn’t wrap his mind around it, but Annabeth had taken to the idea like a fish to water. She hadn’t stopped asking questions since they had sat down in a quiet booth in a relatively uncrowded restaurant. 

“Okay, explain it to me again,” Hermione said, when there was finally a pause in Annabeth’s stream of questions. “You know Luna is a … demigod” — she said the word like she was testing it out — “because she could see that the dogs weren’t dogs?”

“They weren’t dogs,” Percy said. “They were monsters.”

“They looked like dogs to me.”

“Yeah,” he said. “The Mist does that.” He saw Hermione frown, and he continued. “It’s just an old magic protection thing. It makes non-demigods think what they are seeing is something ordinary, or at least explainable, because ordinary humans aren’t capable of understanding something like demons and gods existing.”

“Hermione is not an ordinary human,” Luna piped up, in her melodic voice. Percy had never heard anything quite like it, but it was captivating.

“She’s not,” Annabeth said, “but apparently our magic and your magic don’t actually interact.”

“Except in me.” Luna nodded, and Annabeth smiled.

“Except in you,” she said.

“So if Luna is really a demigod,” Hermione continued. “then her mother is a Greek goddess?”

“Or father,” Percy said. “Poseidon is my dad.”

“My mother,” Luna said. “I know my father. He’s a very wonderful man.”

“Do you know anything about your mother?” Annabeth asked.

Luna nodded. “Yes,” she said. “I have memories of her before she died. Before I thought she died, I suppose. She was beautiful. And very smart. She taught me about art and weaving and literature. She was elegant, too, graceful.” Luna paused, her eyes glazing over just slightly as she thought back. “She had gray eyes,” she said. “I always wished I did too, because they were mesmerizing. Gray eyes and black hair. Long hair.” Luna turned to Annabeth, studying her from across the table. “She looked a little like you actually.”

Annabeth didn’t answer, but for some reason, Luna’s revelation was the least surprising thing that had happened all day. Percy laughed. All three women looked at him.

“What?” Hermione said.

“Athena.” Annabeth answered before he could, apparently finding her words. “Your mother is Athena. Same as mine. You are my sister. My half-sister.”

The words seemed to hang in the air, floating above the table, encompassing all four of them. The silence between them was almost beautiful.

“I have a sister,” Luna breathed out eventually. She looked almost amazed.

“Technically,” Annabeth said. “You have a lot of sisters. And brothers. There are quite a few of us.”

“This is unbelievable,” Hermione said. She was looking between Luna and Annabeth. It was hard to deny, though. Now that the truth was out there, Percy could see it. Luna and Annabeth, they really did look like sisters might look — even sisters who came from a deity and two very different fathers. 

Hermione continued, “I feel like everything I thought I knew was just turned upside down.”

Percy couldn’t help himself. He laughed at that. “Welcome to our life,” he said. “It’s quite the adventure.”

Hermione didn’t look like she really loved that idea, but Luna smiled. “I can’t wait.” Judging from the expression on Annabeth’s face, Percy knew she couldn’t wait either. As for him and Hermione? They would both just have to be along for the ride.

Percy placed his hand on top of Annabeth’s, which was lying on the table. “I guess we all have a lot to talk about,” he said. Annabeth reached out her other hand across the table to take Luna’s. “We really do,” she said.

Luna’s smile grew wider. “Ready when you are.”


End file.
